Reel mowers use a scissoring action to shear grass and like foliage, rather than tearing the leaves. Such reel mowers are more expensive and require more maintenance than rotary mowers, however they are preferred by golf courses and the like where appearance and healthy grass are important. Individual reel mower assemblies are quite narrow, and consequently reel mower units commonly comprise a plurality of side-by-side reel mower assemblies.
Examples of such mowers are disclosed in U.S. Pat. Nos. 5,291,724, 5,477,666, and 6,318,059. In a typical reel mower assembly, an attachment member, commonly called a bed bar, is attached to the apparatus in rigid relationship to the reel, and a replaceable bed knife is attached to the bed bar. The reel, bed bar and bed knife are oriented such that the bed knife is held parallel to the reel axis and in close proximity to the reel knives so that a shearing action is achieved between the reel knives and the bed knife. Typically an adjustment mechanism is provided to allow movement of the bed bar relative to the reel so that the bed knife can be moved into proper relationship with the rotating reel knives.
Conventionally, the bed knife is attached to the bed bar with a plurality of screws placed through holes in the bed knife and engaging threaded holes in the bed bar. Typically ten or more screws are used. Changing the bed knife requires that these screws be removed, and then replaced. Typically the bed knife is attached to the underside of the bed bar so that the apparatus must be raised sufficiently, or partially dis-assembled, to allow access to the underside of the reel mower assembly to remove the screws and the bed knife. A reel mower unit such as is used by a golf course or the like may comprise eight or ten individual reel mower assemblies, and changing bed knives on such a mower unit requires significant labor time and corresponding downtime.
As well, the screws fix the bed knife to the bed bar such that when a stone or similar debris enters the mower, it can jam between the fixed bed knife and the reel, causing damage to one or more portions of the apparatus. Similarly should the bed knife contact a substantially buried obstruction, the bed knife can be damaged as it bounces over the obstruction. While the bed knife can simply be replaced, damage to the reel is generally much more costly and problematic, given the close tolerances required for proper operation.